Colonel Muammar Gaddafi is confronting the most serious challenge to his 42-year rule as leader of Libya by unleashing his army on unarmed protesters.

Unlike the rulers of neighbouring Egypt, Gaddafi has refused to countenance the politics of disobedience, despite growing international condemnation, and the death toll of demonstrators nearing 100.

The pro-government Al-Zahf al-Akhdar newspaper warned that the government would “violently and thunderously respond” to the protests, and said those opposing the regime risked “suicide”.

William Hague, the UK’s foreign secretary, condemned the violence as “unacceptable and horrifying”, even as the Libyan regime’s special forces, backed by African mercenaries, launched a dawn attack on a protest camp in the eastern Libyan city of Benghazi.

Britain is scrambling to extricate itself from its recently cosy relationship with Gaddafi, initiated by then prime minister Tony Blair in 2004. That rapprochement saw Libya open its doors to British oil companies in exchange for becoming a new ally in the “war on terror” while Britain sold Gaddafi arms.